Englishmen race to find the tomb of Ghengis Khan. They have to get there fast, as the evil genius Dr. Fu Manchu is also searching, and if he gets the mysteriously powerful relics, he and his diabolical daughter will enslave the world!

Fu Manchu: I am a doctor of philosophy from Edinburgh, a doctor of law from Christ's College, a doctor of medicine from Harvard. My friends, out of courtesy, call me 'Doctor'.

Sir Lionel Barton: You're Fu Manchu, aren't you? Fu Manchu: I am a doctor of philosophy from Edinburgh, I am a doctor of law from Christ College, I am a doctor of medicine from Harvard. My friends, out of courtesy, call me doctor. Sir Lionel Barton: Oh, I beg your pardon. Well, three times doctor, what do you want of me. Fu Manchu: I have sent for you to make your fortune. What good are these relics of a dead warrior to you? Sir Lionel Barton: Oh, our English people like to look at them on holidays. Fu Manchu: Are they worth a million pounds to you? Sir Lionel Barton: My dear fellow, I can't sell what I haven't got. Fu Manchu: But you will tell me where they are for money, I mean? Sir Lionel Barton: Not for anything in the world.

Nayland Smith: What do you expect to find in that tomb? Sir Lionel Barton: A record, the golden plate, the threat of Genghis Khan's return, the golden mask he wore, and the famous golden scimitar. Nayland Smith: Exactly, of course in your hands these things would be merely interesting archaeological specimens to go into British Museum, but should Fu Manchu put that mask across his wicked eyes and take that scimitar into his bony, cruel hands, all Asia rises. He'll declare himself Genghis Khan come to life again. And that, my friend, is what you have got to prevent. You must find that grave, and you must be the first to find it. And you must bring those pretty things back to England.

Fah Lo See: I have seen a vision, the prophecy is about to be fulfilled. Genghis Khan, masked in his plate of gold, bearing the scimitar that none but he could ever wield comes back to us. I've seen a vision of countless hordes swarming to recapture the world. I've seen them victorious. I've heard the shouts of the dead and the dying drowned by the victorious cries of our people. Genghis Khan comes back! Genghis Khan leads the East against the world!

Movie Trivia:

Charles Vidor started directing this movie but was fired after a few days of shooting and replaced by Charles Brabin.

It took Boris Karloff 2.5 hours every morning to apply makeup for this role.

As originally scripted, during the torture sequence, it was planned to have Von Berg (Jean Hersholt) suspended over the crocodile pit and Neyland Smith (Lewis Stone) about to be impaled by the walls of spikes. This was reversed when, for reasons unknown, it was thought that a fat captive would make more sense being impaled than a thin one.

MGM once considered Clark Gable for the part later played by Charles Starrett.